Anhydrous aluminum antiperspirant powder aerosol compositions and methods of preparation



United States Patent Melvin Arthur Goldberg, West Englewood, and William Roy Netzbandt, Dumont, NJ assignors to Lever Brothers Company, New York, N.Y., a corporation of Maine No Drawing. Filed May 1, 1962, Ser. No. 191,446 8 Claims. (Cl. 16790) This invention relates to an antiperspirant; and more particularly, it is concerned with an aerosol antiperspirant powder spray.

It is known to provide an antiperspirant in the form of a cream, a stick and a roll-on. However, these products have certain disadvantages since they may cause staining and dye bleeding on fabrics, may leave an undesirable feel on the skin, and may have excessive quantities of alcohol and soap therein. It is also known to dispense a liquid antiperspirant spray from a plastic squeeze bottle but the applied antiperspirant may run on the skin; this is also commercially undesirable.

In the past, an antiperspirant has been used in powdered form. However, there'has been considerable difiiculty in applying the powdered antiperspirant satisfactorily to the skin from the usual containers therefor. Although aerosol powder sprays have been in commercial existence, prior to this invention a suitable antiperspirant in the form of an aerosol powder spray could not be prepared.

It has now been discovered that an aerosol antiperspirant powder spray can be provided by forming a dispersion comprising an altuninum compound, an alcohol and a propellent. This dispersion is passed through a screen and the screened dispersion is subsequently packaged in an aerosol can under pressure. A spray of anti-perspirant is dispensed therefrom as desired and a substantially dry product is provided when it strikes the skin.

It is critical in the present invention to prepare a dispersion with an aluminum compound therein which is in fine particulate form and of a size sufficiently small to provide adequate coverage of the treated skin area. An aluminum compound, which has a particulate size to pass through a 200 mesh or finer screen, is suitable; however, finer sizes are preferred for better skin coverage and less likelihood of valve clogging. The preferred aluminum compounds pass through a 325 or finer mesh screen which avoids clogging in the currently available valves. Furthermore, an aluminum compound is defined herein as a compound which is not soluble in propellant and which has antiperspirant and astringent properties. Preferred compounds are aluminum chlorhydrate (aluminum chlorhydroxide complex) and aluminum sulfate. Aluminum chloride is also suitable for use in the practice of the invention provided that the dispersion is prepared and packed under strictly anhydrous conditions. It is also critical to use from about 4 to 10% of the aluminum compound, e.g., aluminum chlorhydrate, based upon the total weight of the aerosol antiperspirant powder spray. A larger amount is too dusty when sprayed and clogs the aerosol valve; and a smaller amount is relatively ineffective as an antiperspirant.

3,28%,581 Patented Nov. 29, 1956 ice Esters Within the purview of this invention, which are generally incorporated into the aforementioned dispersion, have the general structure:

wherein R is an aliphatic hydrocarbon group having 12 to 18 carbon atoms; R is selected from the group con sisting of an aliphatic hydrocarbon having 3 to 18 carbon atoms and an alkyleneoxy group having a terminal OH and having the formula (R"O) H wherein R" is an alkylene having at least 2 carbon atoms, n is an integer from 1 to 9, and the product of R" and n is from 3 to 18; and the sum of carbon atoms in R and R is from 15 to 34. Specific esters within this generic structure include isopropyl myristate-palmitate, propylene glycol monooleate and stearyl palmitate. The presence of an ester within critical limits facilitates dispersion of the powder and in particular makes it easier to re-disperse any powder that may settle on standing. It has been found that from 2 to 5% esters based upon total weight of spray is the operable range; more than 5%, e.g., 6%, provides a powder film which is too wet and less than 2%, e.g., 1%, provides little observable benefit.

Alcohol is also a critical component in the instant dispersion. Any known commercial alcohol, e.g., an admixture of 5 parts of methyl alcohol and 100 parts of 200 proof ethyl alcohol, is applicable. However, the range of alcohol required for the success of the present invention is 2 to 4 wt. percent based upon the total spray. The resultant spray is too wet if a higher alcohol c0n tent is employed and there is powder agglomeration if a lower alcohol content is used. Besides the specific commercial alcohol heretofore disclosed, the lower aliphatic alcohols are suitable provided the alcohol is soluble in propellent which includes the following: methanol, ethanol, n-propanol, isopropanol, propylene glycol, diethylene glycol and mixtures thereof.

The dispersion generally has a non-irritating germicide included therein within the range of 0.05 to 1.5 wt. percent based upon the total spray. The following germicides among others are suitable: 3,4,5 tribromosalicylanilide, hexachlorophene [2,2'-methylene-bis(3,4,6-trichlorophenol)], benzalkonium chloride (alkyl-dimethylbenzyl-ammonium chloride), 3,4,4'-trichlorocarbanilide and 2,2,3,4-tetrabromosalicylanilide.

It is critical in the instant invention to add at least one liquefied gaseous propellent to the dispersion prior to the screening operation. Dichlorodifluoromethane and 1,2-dichloro-l,1,2,2-tetrafluoroethane are suitable and either of them can be used as the only propellent in the system. Trichloromonofiuoromethane is also suitable but it must be employed in an admixture with another propellent, e.g., an admixture of 50% dicholrodifiuoromethane and 50% trichloromonofluoromethane. The trichloromonofluorometh-ane may also contain 0.3 nitromethane to inhibit acid formation. The aforementioned propellents, e.g., halogenated hydrocarbon propellents, comprise the balance of the aerosol antiperspirant powder spray, which is generally between 79 and based upon the total weight of the spray.

Although not essential for this invention, a perfume compound is usually included in the dispersion within 813 the range of .01 to .04%. The perfume can be any one which is known in the art. For example, the following perfumes are satisfactory: oil of lavender; oil of sandalwood; ylang-ylang; geranium; patchouli; and mixtures thereof. These perfumes can be employed alone or in blends with other materials.

After the dispersion with the aforementioned components has been formed, it is passed through a screen, such as a stainless steel screen with a mesh of at least 325. During this screening operation, the absorption of moisture should be avoided and agitation should be provided. The necessity for screening dry powder through a fine screen presents practical difficulties. Sufiicient dry powder can be screened for small batches if ample time is available for the screening operation, but it is impossible with the large scale production of the instant composition. We have discovered, however, that a dispersion can be screened readily on a large scale; this overcomes the necessity of screening the dry powder and makes this invention commercially feasible.

The screened dispersion is generally collected in a jacketed holding tank. However, a plain tank may be used with the screened dispersion being recirculated through a heat exchanger. The dispersion is thereby cooled to the desired temperature, e.g., 20 F. or less.

The cooled dispersion is subsequently incorporated into an aerosol can. Additional propellents, besides those included in the dispersion, may also be independently incorporated into the can. For example, if trichloromonofluoromethane is employed in the dispersion, dichlorodifluoromethane may be added to the aerosol can after the dspersion is packaged therein. A valve is then crimped on the aerosol can containing the dispersion and, optionally, the additional propellents. When the additional propellents are introduced through the valve after crimping, the dispersion need not be cooled below room temperature. As desired, the contents in the can are dispensed therefrom to provide an aerosol antiperspirant powder spray on the skin.

Thus in accordance with the present invention, it is now possible to form an antiperspirant which is an aerosol powder spray. Some of the components in the instant end product have been used in other forms of antiperspirant (U.S. Pat. Nos. 2,492,085 and 2,890,087). However, the success of this invention is dependent upon adhering to the critical limits of components therein and by following the required processing conditions. For example, it is essential that the dispersion be eflicient enough to prevent rapid settling of the solid particles.

The following examples are submitted to illustrate but not to limit this invention. Unless otherwise indicated, all parts and percentages in the specification are based upon weight.

Example 'I The following components were used to prepare an aerosol antiperspirant powder spray.

Wt. percent 1 Consists of 200 proof ethyl alcohol containing 5 gallons of methyl alcohol for every '100 gallons of ethyl alcohol appearance, clear, colorless liquid odor, equal approved sample specific gravity, .7938 wt./gallon, 6.60 pounds ethyl alco- 1101 by volume, 95.2% moisture 0.00, 0. 1%.

Example 11 An aerosol antiperspirant spray was provided from the ingredients listed herebelow.

Ingredient: Wt. Percent Chlorhydrol, impalpable powder 8.00 Deltyl Extra 2 2.00 TBS 0.05 Alcohol per Example I 4.00 Perfume 0.03 Propellent l1 (trichloromonofluoromethane 42.96 Propellent 12 (dichlorodifluorometha-ne 42.96

Aluminum chlorhydroxide complex; analysis shows aluminum oxide (A1203), 47.0i-1.0% chlorides (*CI), 16.3% i0.5%; sulphates (S04), .05% max.; heavy metals (as Pb), p.p.m. max. arsenic (AS203), 2 ppm. max.; iron (as Fe), 0.1% max; Al Cl atomic ratio, 2.1: 1; pH of 15 sol.,h4.5 m1n.; specific gravity, 1.9 and 97% passes thru 325 mes Givaudan Delawanna predominantly isopropyl myris ta'te, with a small amount of isopropyl esters of other saturated fatty acids; color, colorless liquid; odor, practically odorless; Sp. Gr. at 25 (3., 0850-0854; Ref, Index at 20 6., 1.435- 1.438; M.P., +5.0 0.; acid value, 1.0 mg, KOH/gm.; sap. value, 202-210 mg. KOH/gm.; iodine value, 1.0 max.

The TBS was dissolved in the alcohol while warming slightly. The Deltyl and perfume were added with subsequent cooling to below 74 F. Liquefied propellent 11 and chlorhydrol were consecutively incorporated into the system in conjunction with agitation. The resultant dispersion was passed through a 325 mesh stainless steel screen with continuous stirring into a jacketed holding tank which was also equipped with an agitator. The screened dispersion was cooled to 20 F. and loaded into aerosol cans. Liquefied propellent 12 was then added to the cans. Immediately thereafter, valves were crimped onto the cans.

It should be noted that it is important not to pick up moisture during the steps in this procedure. Furthermore, the dispersion should be kept well-stirred during the straining, holding and filling steps.

A suitable packaged end product was obtained in this example.

Example III An aerosol antiperspirant powder spray was formed from the components indicated herebelow following the same procedures described in Example II.

Components: Wt. Percent Chlorhydrol, impalpable powder 8.00 Deltyl Extra 2.00 Alcohlol, SDA No. 40, anhydrous 1 4.00 Hexachlorophene (G-ll) 0.08 Perfume 0.03 Propellent 11 42.945 Propellent 12 42.945

lo every gallons of ethyl alcohol add 3 ounces of bfllclllli or brucine sulfate, NF IX, and gallon of t-butyl a co 1o When dispensed from an aerosol can, a dry powder spray was provided on the skin.

Example IV Antiperspirants (Wt. percent) Ingredients Aluminum chlorhydratc Alcohol per Example I Freon ll-3 1 Propellent 1 Isopropyl myristate. Stearyl palrnitate Z Propylene glycol monooleate.

l Pro ellent 11 with 0.3% nitromethane. 2 Cr5 srfi-OCraHa7 Each of the above aerosol antiperspirants formed a satisfactory dry powder when dispensed on skin.

Example V Antiperspirants D, E, F, G and H were formed from dispersions with the following ingredients therein.

Antiperspirant (Wt. percent) Ingredients D E F G H Chlorhydrol 8. 10. 00 8. 00 8. 00 8. 00 Isopropyl myristate 2. 0O 2. 00 2. 00 2. 00 2. 00 Alcohol per Example L- 4. 00 4 00 4. 00 4. 00 Talc 8. 00 Gll TB S. 0. lerfume. 0. 01 Propellent l1 38. 54 Propellent 12 42. 945 26. 39 25 79 34. 42 39. 40 Propellent 114 2 51. 46

1 Not included in the dispersion initially. 2 Same as Freon 114.

After screening and cooling as described in Example II, the dispersions were incorporated into aerosol containers by gravity flow. Cold propellent 12 was then incorporated into the containers and valves were crirnped thereon.

The containers were subjected to steam testing at 125 to 135 F., and then to water-bath testing at about 95 F. After being subjected to these tests, the containers were capped.

Satisfactory antiperspirant powder sprays were subsequently dispensed from aerosol containers with antiperspirants D, F, G and H. However, there was powder agglomeration in antiperspirant E which did not have alcohol included therein.

Example VI The following components were used to form an aerosol antiperspirant powder spray.

Component: Wt. percent Cblorhydrol 8.00 Deltyl 2.00 Alcohol per Example I 4.00 TBS 0.05 Perfume 0.004 Propellent 11 42.146 Propellent 12 43.80

The procedures for providing a dispersion and a packaged aerosol container therefrom were similar to those described in Example II.

A commercially suitable antiperspirant in the form of a powder spray was obtained when the contents were dispersed from the aerosol can.

Having set forth the general nature and specific embodiments of the present invention, the scope is now particularly pointed out in the appended claims.

What is claimed is:

1. A composition under pressure for providing an aerosol antiperspirant powder spray on the skin which comprises about 4 to 10 parts of an aluminum compound which is not soluble in propellent and which has antiperspirant properties, said aluminum compound being aluminum chlorhydroxide complex, aluminum sulfate or aluminum chloride; about 2 to 4 parts of a lower aliphatic alcohol; and 79 to 94 parts of a liquefied gaseous propellent; said composition having been screened as an anhydrous dispersion of aluminum compound in propellent with a screen not larger than 200 mesh.

2. The composition according to claim 1 which also contains a germicide, a perfume and an ester having the general structure:

wherein R is an aliphatic hydrocarbon group having 12 to 18 carbon atoms; R is an aliphatic hydrocarbon having 3 to 18 carbon atoms; and the sum of carbon atoms in R and R is from 15 to 34.

3. A composition under pressure which comprises about 4 to 10 parts of an aluminum compound which is not soluble in propellentand which has antiperspirant properties, said aluminum compound being aluminum chlorhydroxide complex, aluminum sulfate or aluminum chloride; about 2 to 5 parts of an ester which is isopropyl myristatepalmitate, propylene glycol monooleate or stearyl palmitate; about 2 to 4 parts of a lower aliphatic alcohol; about 0.05 to 1.5 parts of a gennicide; about 0.01 to 0.04 part of a perfume; and about 79 to 94 parts of a liquefied gaseous propellent; said composition having been passed through a screen not larger than 325 mesh as an anhydrous dispersion of aluminum compound in propellent; said composition being packaged in an aerosol container for dispensing a dry antiperspirant powder spray on the skin.

4. A composition under pressure for providing a dry aerosol antiperspirant powder spray on the skin which comprises 8 parts of aluminum chlorhydroxide complex which is not soluble in propellent and which has antiperspirant properties, 2 parts of isopropyl myristate, 0.03 part of perfume, 4 parts of ethyl alcohol, 0.08 parts of 2,2-methy1ene-bis(3,4,6-trichlorophenol) and 42.945 parts of liquefied gaseous trichlor-omon-ofiuoromethane as a pro pellent; said composition having been passed through a 325 mesh screen as an anhydrous dispersion of said aluminum compound in said propellent and subsequently cooled; said composition being packaged in an aerosol container with 42.945 parts of liquefied gaseous dichlorodifiuoromethane.

5. A process for forming an aerosol antiperspirant powder spray for dispensing from an aerosol container to provide a dry antiperspirant on the skin which comprises preparing an anhydrous dispersion comprising about 4 to 10 parts of an aluminum compound which is not soluble in propellent and which has antiperspirant properties, said aluminum compound being aluminum chlorhydroxide complex, aluminum sulfate or aluminum chloride, about 2 to 4 parts of a lower aliphatic alcohol and about 79 to 94 parts of a liquefied gaseous propellent; passing said dispersion through a screen not larger than 200 mesh; and packaging said screened dispersion in an aerosol container.

6. The process according to claim 5 in which also incorporated into the dispersion is a germicide, a perfume and an ester having the general structure:

wherein R is an aliphatic hydrocarbon group having 12 to 18 carbon atoms; R is an aliphatic hydrocarbon having 3 to 18 carbon atoms; and the sum of carbon atoms in R and R is from 15 to 34. v

7. A process for forming an aerosol antiperspirant powder spray for dispensing from an aerosol container to provide a dry antiperspirant on the skin which comprises preparing an anhydrous dispersion comprising about 4 to 10 parts of an aluminum compound which is not soluble in propellent and which has antiperspirant properties, said aluminum compound being aluminum chlorhydroxide complex, aluminum sulfate or aluminum chloride, about 2 to 5 parts of an ester which is isopropyl myristatepalrnitate, propylene glycol monooleate or stearyl palmitate, about 2 to 4 parts of a lower aliphatic alcohol, about 0.05 to 1.5 parts of a germicide, about 0.1 to 0.4 part of a perfume and a liquefied gaseous first propellent; passing said dispersion through a screen not larger than 325 mesh; cooling said screened dispersion to a temperature below 20 F.; packaging said cooled dispersion in an aerosol container; and incorporating subsequently a liquefied gaseous second propellent into said container with said dispersion therein whereby the total propellent in 1 8 fume, 4 parts of ethyl alcohol, 0.08 part of 2,2'-mcthylenebis(3,4,6-trichlorophenol), and 42.945 parts of liquefied gaseous trichlorofluoromethane; passing said dispersion through a 325 mesh screen; cooling said screened dispersion to a temperature below the boiling point of dichlorodifluoromethane; packaging said cooled dispersion in an aerosol container; and incorporating subsequently 42.945 parts of dichlorodifluoromethane into said container with said dispersion therein.

References Cited by the Examiner UNITED STATES PATENTS 2,823,169 2/1958 Brown 167-90 2,872,379 2/ 1959 Neumann 16790 2,959,325 11/1960 Beard 222--1 3,014,844 12/1961 Thiel 16739 3,088,874 5/1963 Geary 167--39 OTHER REFERENCES Sheperd: Aerosols, Sci. and Tech. Interscience Pub., N.Y., 1961, pp. 38-40, 286-287, 350, 351, 360-363, 393.

Armstrong: Soap and Chem. Spec. 34: 12; December 1958, pp. 132, 133.

JULIAN S. LEVITT, Primary Examiner.

' FRANK CACCIAPAGLIA, ]R., Examiner.

A. P. FAGELSON, V. C. CLARKE, Assistant Examiners. 

1. A COMPOSITION UNDER PRESSURE FOR PROVIDING AN AEROSOL ANTIPERSPIRANT POWDER SPRAY ON THE SKIN WHICH COMPRISES ABOUT 4 TO 10 PARTS OF AN ALUMINUM COMPOUND WHICH IS NOT SOLUBLE IN PROPELLANT AND WHICH HAS ANTIPERSPIRANT PROPERTIES, SAID ALUMINUM COMPOUND BEING ALUMINUM CHLORHYDROXIDE COMPLEX, ALUMINUM SULFATE OR ALUMINUM CHLORIDE; ABOUT 2 TO 4 PARTS OF A LOWER ALIPHATIC ALCOHOL; AND 79 TO 94 PARTS OF A LIQUEFIED GASEOUS PROPELLENT; SAID COMPOSITION HAVING BEEN SCREENED AS AN ANHYDROUS DISPERSION OF ALUMINUM COMPOUND IN PROPELLENT WITH A SCREEN NOT LARGER THAN 200 MESH. 